1. Field of the Invention
The present invention pertains to the winding of filaments such as wire or optical fibers, and more particularly to apparatus for winding such filaments rapidly and without placing undue stress and strains on the filament.
2. Description of Related Art
There are numerous circumstances in which an extended length of a filament (e.g., wire or optical fiber) is wound onto a bobbin or drum portion of a missile, for example, in order to provide a data link during use. Such filaments throughout their storage and as well as during winding must not be subjected to stresses or strains exceeding a certain amount since otherwise the transmission of data can be substantially impaired.
In addition to winding an actual filamentary data link, filament winding apparatus is used in testing facilities where the filament is payed out at missile flight speed for test purposes. For this purpose, it is also important that the filament not be stressed since this would degrade test results.
Existing drum filament payout machines have turbine-driven drums on which the filament is wound to pay it out from a dispenser at a desired speed (e.g., missile flight speed). A primary disadvantage of such machines is that the end of the filament attached to the drum is not directly available to permit transmission testing during payout. Also, centrifugal loading on the wound up fiber threatens its physical survival during test and may contribute to optical loss during payout.
It has been suggested in the past that filaments be wound onto a stationary drum in the manner of the spin-casting reel used by fishermen. Although it is not known whether or not this has actually been attempted, there would be at least two obstacles to be overcome, namely, (1) the filament would have to make three turns (out from the axis, back parallel to the axis and inward to the drum surface), since pulleys are impractical at payout speeds and friction at a fixed eyelet will produce excessive heating and wear, and, (2) the extreme centrifugal loads would present a severe structural design challenge for the cantilevered bail arm.